For quite some time, builders of homes and commercial buildings have used preformed truss systems as a part of the construction of a building. These truss systems are used to span the space between opposed supporting structures, such as to span the space between opposing walls of a building to support its floor. Another, more frequent use of truss systems is to span the distance between opposed supporting walls as part of a roof system of a house or commercial building.
Typically, a truss system is anchored at each end to a supporting wall, and spans the distance between the opposing walls. The truss systems used for supporting a floor comprise an array of truss units, each of which has a fiat, upper surface disposed in a horizontal plane. When the truss units are assembled into a truss system, the upper surfaces of the truss units form a plurality of generally co-planar support surfaces over which the floor decking can be placed and to which the floor decking can be attached.
Unlike floor truss systems, roof truss systems take a variety of shapes. Although some roof truss systems provide a plurality of planar, horizontally disposed support surfaces for buildings having flat roof systems, many buildings have roofs, which although planar, are not horizontally disposed. For example, many residential buildings have peaked roofs wherein the roof surface comprises a pair of angled planes having an apex at the crown of the roof. The pitch of a roof can be either more or less steep (i.e., having relatively greater or lesser angle from horizontal) depending upon the desires of the architect or building designer.
Examples of various truss systems and truss units are shown and discussed in TRUSS PLATE INSTITUTE Commentary and Recommendations for Handling, Installing and Bracing, Metal Plate Connected Wood Trusses, HIV-91, the TRUSS PLATE INSTITUTE, 583 D'Onofrio Dr., Suite 200, Madison, Wis. 53719 (1991) (the "TPI HANDBOOK").
One difficulty that occurs with truss units is stabilizing and bracing them units after they are attached to the supporting walls, and before the decking is applied. A typical construction process by which a truss system is assembled is described below. First, individual truss units are shipped to the construction site. At the construction site, the supporting walls are formed, and generally include an upper supporting beam on each of the upright supporting walls. The truss units are then placed on their ends and attached to the upper supporting beams, to span the space between opposing walls. A plurality of truss units are arrayed in a row from one end of the supporting walls to the other end of the supporting walls.
Most truss units have a much greater height dimension than a width dimension. As such, a truss unit that is supported only at its base by its attachment to a supporting wall is prone to topple over on its side, much like a coin placed on its edge is prone to fall over onto its side.
To prevent the truss units from toppling over on their sides, and to provide support for the truss units so that the construction crew can attach either the floor decking or the roof decking (as appropriate) to the upper surface(s) of the truss units, it is often desirable to brace the truss units to prevent them from falling over like a row of dominos. Several brace systems and brace schemes are known for performing this function, many of which are shown in the TPI HANDBOOK.
At page 36 of the TPI HANDBOOK, a ground bracing system is shown that comprises a plurality of stakes that are driven into the ground adjacent to the side of a building. A series of diagonal bracing members extend from the ground stakes to the first truss unit to support the first truss unit in an upright position. Additionally, a vertical brace may be attached to the ground brace to provide additional bracing. A series of laterally extending brace members extend generally perpendicular to the truss units to extend between adjacent truss units. These laterally extending brace members are attached to the upper surface of the truss units, and typically comprise 2".times.4" wood boards which are nailed to the upper surfaces of the truss units. Once the truss units are so braced, the construction crew can then install the decking, which itself attaches to the upper surfaces of the truss units. As will be appreciated, the decking also provides bracing for the truss units. As a decking is applied, the lateral brace members can be removed successively, until the decking is placed over the entire array of truss units to create the deck of the roof. When all of the decking material is in place over the array of truss units, the lateral stability provided by the decking obviates the need for the ground bracing, which can then be removed.
As best shown at pages 46-49 of the TPI HANDBOOK, the laterally extending brace members can also be joined by diagonally disposed brace members to provide additional support for the truss units.
An additional known bracing system is the TRUSLOCK spacing tool manufactured by Truslock, Inc. of Route 1, Box 135, Calvert City, Ky. 42029, which is shown in their sales brochures. The TRUSLOCK tool comprises a plurality of tool segments each of which is designed to extend between a pair of adjacent truss units. Each tool segment includes a flange at each end for engaging a side surface of a truss unit. The TRUSLOCK tool also includes a rivet that connects adjacent tool members to permit adjacent tool members to pivot about each other, and to permit the segments to fold up about each much like a foldable measuring stick. The TRUSLOCK spacing tool is also believed to be shown in Jarvis U.S. Pat. No. 4,322,064.
Another known truss system accessory is the KANT-SAG.RTM., TSX Truss Spacer manufactured by United Steel Products Company of 703 Rogers Drive, Montgomery, Minn. 56069. The KANT-SAG.RTM. device is not a truss brace system, but merely a truss spacer system. The KANT-SAG.RTM. Truss Spacer comprises an elongated spacing device that is capable of spanning the distance among or between a plurality of truss units. At predetermined intervals, the spacing device includes an opening to permit the spacer to be fit over and to receive beam members of the truss unit. Adjacent to the opening is a aperture through which the spacing device can be nailed to the upper surface of a bem of the truss unit.
Although the devices discussed above most likely perform their intended function in a workmanlike manner, room for improvement exists. In particular, although the TRUSLOCK system functions as a truss spacing and bracing tool, the configuration of the device permits it to be installed on a roof only on a temporary basis. Because the device includes a portion which extends above the plane formed by the upper surfaces of the beams of the truss unit, the TRUSLOCK device is designed to be installed prior to the installation of the decking, and must be removed before the decking can be installed on that portion of the truss unit wherein the TRUSLOCK system resides. This need for removal of the tool can increase the labor costs associated with the use of the tool, when compared to devices which need not be removed.
The KANT-SAG.RTM. system appears to be configured so that it may be connected between the truss units on a permanent basis, with the decking being capable of overlaying the KANT-SAG.RTM. truss spacer when it is in place on the roof unit. However, its configuration makes it unsuitable for use in bracing. Rather, the KANT-SAG.RTM. truss spacer can only be used to maintain the truss units at a proper spaced distance from each other, and, according to KANT-SAG.RTM.'s literature, can not be relied upon to provide bracing for the truss units.
Because of these deficiencies noted above, room exists for improvement by providing a bracing system which can be permanently installed on to truss units to allow the installation of decking with the bracing unit in place to reduce labor costs, but yet which is strong enough to provide an acceptable level of bracing in addition to the spacing function served by the truss brace.
It is therefore one object of the present invention to provide an improved truss brace system that provides both a bracing and a spacing function, but which can be permanently installed onto a truss unit system to thereby obviate the need for removal of the truss braces, and thereby reduce the labor costs associated with the removal of the bracing units from the truss system.